# SDR ASAA2022030537634

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: March 5, 2022
- Submitted: March 9, 2022
- Operation: Air carrier
- Aircraft: [N514AS](https://openairdocs.org/aircraft/N514AS), registered now
- Make and model: Boeing 737890
- Aircraft serial: 35193
- Aircraft time: 48,405 hours, 14,275 cycles
- System (JASC): [2130 · Cabin Pressure Control System](https://openairdocs.org/jasc/2130)
- Part: Modulating Valve
- Part number: 3989083
- Part serial: 2173
- Condition: Faulty
- Location: Left Ecs Bay
- Part time: 84,344 hours, 42,629 cycles
- Stage of operation: NR
- How discovered: V
- Nature of condition: J
- Precautionary procedure: O
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/ASAA2022030537634

## Discrepancy

CONT CABIN ZONE TEMP CONTROLLER ILLUMINATES WITH MASTER CAUTION RECALL. LIGHTS EXTINGUISH WITH MASTER CAUTION RESET. GROUNDED - YES. CONFIRMED THAT CONT CABIN ZONE TEMP LIGHT ILLUMINATES W/ MASTER CAUTION RECALL. ACCOMPLISHED PACK TEMP CONTROLLER BITE REF B737-800 FIM 21-62 TASK 801. (R) PACK/ZN CONTROLLER FAULTED FLT DECK TRIM VALVE. REPLACED (CONT CAB) ZONE TRIM AIR MODULATING VALVE REF B737-800 AMM 21-61-21-000/400-801. LEAK CHECK GOOD. ALL TESTS PASSED. ZONE TEMP LIGHT NO LONGER ILLUMINATES W/ MASTER CAUTION RECALL. PACK TEMP CONTROLLER BITE PASSED REF FIM 21-62 TASK 801.

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